One of the problems of synthetic is the life cycle including its reliance on non-renewable fossil fuels as a raw material and for energy use. The use of synthetics continues to grow, mostly due to polyester – which currently makes up 60% of the fibres used in clothing.This has serious consequences for the climate, perpetuating the demand for fossil fuels as a raw material and using large amounts of energy for production, with polyester generating three times more CO2 emissions than cotton. One of the problems is that 80 percent used textile and shoes are disposed of from which 56 per cent finished in landfill at their end of life [2] and the rest are incinerated which creates harmful air emissions.

We must protect the planet and its resources for future generations. Since fossil fuels take millions of years to create, they are non-renewable. Once the resources are depleted, we will not be able to extract any more. For this reason, it is important to conserve fossil fuels by using them as sparingly as possible in important uses and finding alternative materials and sources of energy, preventing these valuable resources going to waste.Renewable resources should deliver significant reductions in greenhouse gas emissions compared to fossil-fuel based systems.

The creation of synthetic materials requires the use of large amounts of toxic chemicals. Polyesters use antimony as a catalyst. Antimony is a carcinogen, toxic to the heart, lung and liver and skin. During the Pet production process it is locked into the finished polymer and not a concern in human health, says industry. The problem is antimony is expelled with the wastewater into our rivers. (175ppm can be leached during the dying process.). Countries that can not afford technologies to remove it release antimony to open waters. When polyester is finally incinerated, it is released as a gas (antimony trioxide). And during Pet production it produces a sludge that when incinerated  creates ash which contains antimony, arsenic and other metals.

Ocean pollution from non-biodegradable micro plastic fibres is also a critical problem. Fibres made from petrochemical polymers such as polyester and other synthetic are a big contribution to microplastic fiber pollution, each cycle of a washing machine could release 700,000 fibres into the environment [3] when they are washed, fibres are released, eventually making their way into rivers and seas, where they can potentially take decades to degrade. Microplastics released from synthetics (polyester, acrylic,…) accumulate persistent organic pollutants as chemical toxics as PCB, PAH and DDT which are carcinogens and can introduced in the flood stream of animals, of course in humans too. Recent studies of the plastic waste along the western coast of Sweden found that more than 90 % of the micro plastics found in ocean surface waters (which are themselves a portion of overall marine plastics) consisted of synthetic textile fibres.Microplastic fibres have been found in diverse habitats, including remote polar glaciers.

This affects footwear as there are “cruelty-free/sustainable” sneakers made of PU, recycled PET or polyester which recommend washing machines in the care instructions.

We absolutely reject polyester and acrylic in everyday wear. We think we all have to stop buying it. In the medium term of existing synthetic garments we recommend to stop using it, specially the fleece fabrics. It is true you can use a filter bag but although it reduces significant shedding, not all, once it is captured, it  will be sent to landfill where ultimately still lead to them leaking out into the environment as atmospheric transfer. We agree that polyester could be a useful material for outwear/outdoor technical garment but always wipe out with a cloth.

We want to clarify that all “natural” materials sold as sustainable are not as inoffensive as the industry shows. There are man-made fibers from natural resources such as viscose, modal, rayon and bamboo that chemically are still plant-based and therefore not synthetic. The process used to transform the wood into textile fibers uses toxic solvents such as sodium hydroxide and carbon disulphide in an open system. This is a highly polluting process and releases many toxic chemicals into the air and waterways surrounding production plants. Just lyocell from Lenzing could be considered less harmful  as is produced in a closed loop although this company has a colonialism production approach.

Viscose, together with polyester are the most common fibers used in fast fashion industry.

Various studies all agree that it takes from 33% to 53% less energy using recycling than virgin polyester. But it is still more than five the time energy and two times more CO2 emissions than organic cotton.  Despite the savings of both energy and emissions from the recycling of PET, the fact is that it is still more energy intensive to recycle PET into a fiber than to use organically produced natural fibers – sometimes quite a bit more energy. The demand for used bottles, from which recycled polyester fibre is made, is now outstripping supply in some areas and certain cynical suppliers are now buying new, unused bottles directly from bottle producing companies to make polyester textile fiber that can be called recycled being post-industrial and not post-consumer [4].

The other problem is that most of the rPET requires virgin fibres too and it is mechanically recycled polyester. This kind of recycling process the plastic degenerates when it is heated, so the subsequent iteration of the polymer is degraded so after a 2 down cycled process it is sent to the landfill and where it will hold space for many years or maybe become part of the Great Pacific Garbage Patch  [4].

Using recycled PET textile means reducing energy consumption and CO2 emissions compared to virgin polyester but it is necessary to add filters during the cleaning process and develop techniques that prevent the shedding of polyester micro plastic fibres from these textiles. It cannot be a stand-alone strategy: it should be complemented by other approaches that seek to tackle the release of micro plastic fibers at all stages of manufacture, use and after disposal, or that balance the material mix in favor of sustainably grown, renewable and biodegradable materials. It should not rely on ‘open loop’ sourcing of postconsumer plastic or collected marine plastics, which simply speeds up the conversion of solid material into more bioavailable microfibers that even it could have the counterproductive effect of allowing the packaging industry to avoid taking responsibility for its own circularity challenges. Resolving the huge problem of plastic in the ocean using rPET is limited, and at worst, brands could be using the profile of this problem for green washing. Open loop recycling of waste plastic bottles could also create the unintended consequence of increasing the consumption of single use plastics [2].

More than half of the plastic waste that flows into the oceans comes from just five Asian  countries: China, Indonesia, Philippines, Vietnam and Sri Lanka, one more reason to doubt  about sustainability of recycled pet fibre is most is produced in one of these country, China where is not fully implemented municipal waste management including waste collection, dumping and recycling, so the synthetic waste  of industries where are produced these fibres are been wasted  without  enough environmental standards, now with the ban of import waste plastic from China maybe the brands which  use it don’t have so easily to use non-renewable resources [5].

Our conclusion is using materials from renewable resources is a better option in terms of sustainability taking into account all stages of the material, the use, recycling and the end of the life cycle, it takes much more advantages compared to the fossil–fuel materials.If synthetic and toxic chemicals will be reduced, it would help to reduce the environmental impact helping to the recyclability.

[2]http://www.greenpeace.org/international/Global/international/publications/detox/2017/Fashion-at-the Crossroads.pdf?_ga=2.17411001.1807177868.1516025948-644738448.1514904338

[3] https://www.theguardian.com/environment/2017/sep/06/plastic-fibres-found-tap-water-around-world-study-reveals

[4] http://www.centreforsmart.co.uk/system/downloads/attachments/000/000/002/original/Footwear_recycling_position_paper.pdf

[5] https://oecotextiles.wordpress.com/2009/07/14/why-is-recycled-polyester-considered-a-sustainable-textile/